When the heart beats too fast

Tachycardia is when your heart beats too fast. In adults, that’s generally more than 100 beats per minute. It can last just seconds or for minutes or hours.

Some ventricular tachycardias can be tolerated without serious results. But if the ventricles (the heart’s lower chambers) quiver during tachycardia, that can interfere with the heart’s ability to pump blood. An abrupt loss of heart function, or sudden cardiac arrest, can result, which is a medical emergency. Without immediate treatment, organ damage, organ failure and even death are likely.

When the heart beats irregularly

When you have AFib, an abnormal electrical signal keeps the heart’s chambers from pumping in a synchronized way. This incomplete cycle allows blood to pool in the atria (the heart’s upper chambers). When blood pools, clots can form.

If one of these blood clots leaves the heart and travels toward the brain, it can block a vital artery. This prevents oxygen from reaching the brain via the bloodstream. This causes a stroke. Deprived of nourishment, the affected brain tissue starts to die.

Stroke can be devastating because the parts of the body controlled by the damaged parts of the brain are affected as well. These disabilities are often permanent, because damaged or dead brain cells aren’t replaced.

There are two types of strokes. Ischemic stroke is caused by a blocked blood vessel to the brain. Hemorrhagic stroke is caused by a ruptured blood vessel, which allows blood to escape into the brain tissue.

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